1. Field of the Invention
The present invention relates to bending presses such as press brakes for bending sheet-like wor)qpieces such as sheet metals. More particularly this invention relates to hydraulic bending presses in which the bending tools are operated by hydraulic means.
2. Description of the Prior Art
The closing forces from a press brake endpoints create bed and ram deflection resulting in uneven longitudinal bending forces. The inherent problem of bed and ram deflection (as illustrated in exaggerated form in prior art FIG. 1), occurring as a result of the bending load, creates a variation of the bend angle along the length of the bend of the workpiece. The result is larger clearances and therefore lighter workloading toward the center of the workpiece, with heavier loading at the bending line workpiece edges. The resulting workpieces are thus bent to greater angles toward the edges resulting in longitudinal curvature of the finished workpieces.